Update:
Did my first session in the new room today, a 4 song heavy-rock session, and while I don't think I quite "nailed it" I think I got pretty good results.
Thanks to some great advice from Dave McNair and others I mostly relied on the gear I already knew (Massive Passive, STC-8 and HEDD) but tried little nudges with the other gear including the API 5500, Crane Song Ibis and SSL comp. Didn't mess with the Summit EQ-200 yet as it seems like the user interface has a bit of a learning curve and I've got enough of that going on already!
Some initial reactions:
First off, the Manley Backbone made it really easy to see what each processor was really doing for/to the sound. I like!
I took to the 5500 fairly quickly and I felt comfortable using it without too much second guessing (it's not exactly a complicated EQ!) Ended up using it on 3 out of the 4 mixes.
The Ibis is a little bit touchy in the boost/cut control (I think this is the standard version) and I'm used to being able to completely disable any/all bands like on the MP. Also find the musical notes a little weird, but I'm sure I get used to it quickly. I really liked what the low-cut was doing for some of these mixes. Used it on 2 songs.
I've never had an opportunity to use an SSL compressor before, and while I found it to be quite grabby I ended up keeping it on one song to help tame some peaks and tighten up the low end a touch.
Managed to get through the session without getting all FUBAR'd in Sequoia, which was my biggest fear. Still getting used to having to switch between two different sessions (pitch/catch) to listen between the songs previously done and the one I'm working on.
All in all, I think the clients really liked the new studio and I felt decently comfortable working in the room. For some reason I felt really good about the session even though I know I have a few things to tweak with the songs.
Woot!